MAJOR: IndexTTS-2 TTS engine integration
- Core IndexTTS engine with unified model interface integration
- Auto-downloader for HuggingFace models + GitHub source code
- Engine adapter with emotion support [Alice:angry_bob] syntax
- Cache integration for IndexTTS-2 parameters
- Factory registration for proper model management
MAJOR: Character parser modularization (930 → 300 lines each)
- Split into base_parser.py, language_resolver.py, segment_processor.py, validation.py
- Added emotion support with backward compatibility
- New split_by_character_with_emotions() method for advanced engines
- Flexible tag parsing: [de:Alice:angry_bob] support
- Language disambiguation to avoid Alice vs language code conflicts
- Full backward compatibility maintained
FEATURES:
- IndexTTS-2 emotion disentanglement (speaker vs emotion separation)
- Duration control and precise voice cloning
- Multi-modal emotion control (audio refs, text, vectors)
- Character switching with emotion references
- All official IndexTTS-2 parameters exposed
DOCS: Implementation plan and architectural TODO items added
